2008-2013 Cadillac CTS General Discussion Discussion, HELP: Need a Service Tech's Advice as My AC Evaporator Drain Hose(s) Keep Clogging in Cadillac CTS Second Generation Forum - 2008-2013; My Bumper to Bumper Warranty expires in May and I am worried about a third recurrence of the AC Evaporator ...

My Bumper to Bumper Warranty expires in May and I am worried about a third recurrence of the AC Evaporator Drain Hose(s) getting clogged within seven months. This latest incident resulted in my newly installed carpets to get soaked and water in my right shoe LOL. Gotta laugh. The water comes from both sides above the tranmission tunnel depending on which way you are turning. I do not park under trees as it sits in a parking garage all day at work and I cover the car 80% of the time at home away from my trees. I asked the dealer what is causing the problem to recur, how is debris getting into the box in the first place, what type of debris is in there, and how can I maintain the drains and prevent debris from getting in the box but I get vague answers. I am sure part of it is some residual debris left behind from the prior cleanings and it was a Florida car, which has alot of bugs. After the first cleaning in August, they said there was insect nesting and leaf debris as the main culprit so I figured I won't have the issue again. It happened a second time in December during a rain storm where I was using the climate control to keep the windows clear from fogging up but the dealer blamed a cowl leak for the problem, which they sealed but I think it was clogged drain(s). The third time was last week because of the warm weather and using the AUTO setting like I always do which was calling for the AC compressor. The symptom starts as a trickle type noise heard from the blower wheel or air hitting the rising water in the box and in a day or two, the leaking starts as the box fills up. Is it possible to get into the box to do a thorough cleaning without taking the whole dash apart? Where is/are the drain hose(s) and are they accessed from inside the car or outside. The shop manual shows a hose on the driver side and to the left of the accelerator pedal that connects to the floor but I am not sure if this is accurate. Also, where does the air AND debris come in so I can put some sort of screening in to stop this? The car has a cabin air filter which I thought would catch any debris but how would debris get past the air taken in for the climate control? Is air drawn from another area as well? The cabin filter is properly installed by the way. Any information about this would be deeply appreciated as info. I searched high and low for info about this on the 2008+ CTS and there is not much out there. I still love the car and am trying to get things worked out with it. Thanks Everyone, Robert

I'm really sorry to hear about this continuous frustration for you! Would you ever consider going to an alternative dealer for a fresh opinion on the clogging? I'm happy to assist where I can (please feel free to send me a private message anytime), and I'm sure forum members will chime in shortly with their usual great feedback.

Would you ever consider going to an alternative dealer for a fresh opinion on the clogging? I'm happy to assist where I can (please feel free to send me a private message anytime), and I'm sure forum members will chime in shortly with their usual great feedback.

Best,

Katie
Cadillac Customer Service

Thanks for taking the time to answer but I had another issue that was not taken care of to my satisfaction by one dealer and when I approached a different dealer, they referred me back to the first dealer and did not want to get involved with something that was previously addressed by someone else. I guess I cannot blame them and there is still a customer care case that is open until it is totally resolved but it is being worked on. This car has had many, many issues, especially a couple of leaks from the sunroof drains, five different trunk leaks, and now three AC drain related leaks. This is troubling but I hope someone in this board can give me some good advice on how to keep the drain hose clear and illustrate how debris can enter the condensor box in the first place when there is a cabin air filter. Its nice to know that someone is listeneing.

we had a similar situation today with a car that wasn't draining the hvac properly

the problem seems to be that the drain hole has these flaps that end up getting stuck together by dirt/dust/etc

i think the idea was to use those flaps to keep that kind of stuff out of the hvac drain system but it ends up clogging sometimes like it did for our customer today and for you

what we did to fix it was to rip the flaps out and install a 90 degree drain elbow with a much larger diameter to ensure it doesn't clog up

...

good luck getting your issues fixed loosend

Thanks Chris. If I have those flaps, it very well could be the trouble. Do you know if they did this from the inside of the car or from the exterior where the hose comes out of the sheetmetal? The shop manual for a CTS shows the drain hose on the driver's side of the tranny hump going from the evap box to the floor sheetmetal where it pushes through. Do I just pull the hose out of the evp box and the other end up through the floor to remove it entirely and then pull out the flaps inside of the hose? Did the 90 degree elbow replace the original hose and what was the replacement elbow made out of (rubber or plastic, etc)? Sorry for all the questions.

Thanks for letting me know your dealer situation in greater detail; I am extremely disappointed to hear that you've been going through this. If you'd ever like me to look into your case for you, you can simply send me your case number via PM and I can investigate for you and report back! It sounds like Rippy has stepped up with some great technical advice, as usual, so I'm rooting for you and hoping a fix is imminent.

yes we access it from the engine bay side and i think the more important part of the repair is to get the flaps removed and the type of elbow is not really an issue

good luck,
chris

Are there two drains? My shop manual shows one that goes into the tranny tunnel so I got under the car and there is in fact, a drain that has a rubber piece with four fingers (flaps you are referring?) that goes through a plastic ring and it drips right onto to the top of the transmission. It had a water droplet on the end so I know it is a drain of some sort. It looks like you have to drop the tranny to access it from the bottom because I could not get my hands up in there. The manual says you pull the drain hose out from the top where it is located to the left of the accelerater pedal in top of the tranny hump, if this is the one you mean. If not, I'm looking at the wrong thing and I am sorry if I'm being thick so is there possibly another drain hose that might stick out of the firewall and into the engine bay? My dealer said the flap ends were "trimmed" when I picked it up but darn if I know how it was accessed and the service manager did not know either. I need to keep on top of this problem and keep that drain hose clear.

only one drain ... i just talked to my tech and realized that the other day he was working on a DTS not a CTS ...

i showed him this illustration of your hvac box (drain hose is #32, and drain is #53)

it seems like you've already figured out how to pull the carpet back

he said that you should check to make sure that the drain is cleared out (cut a larger opening if you have to)
also make sure the hose is not blocked and is securely on the box ... you will probably have to do that by feel